STUDENTS ILLUSION OF PROPORTIONALITY IN GRAPHIC REPRESENTATIONS RELATED TO VACUUM VALVES.

Historically most applications of electrical circuits were realized using vacuum valves. In this work we examine the role of students’ illusion in the understanding of graphic representations in an electrical workshop, and, particularly the triode valve. We observe that students who examine graphic representations of valves often end up with erroneous conclusions as regards their operation because of the illusion of proportionality. Thus, also for vacuum valves, the students apply a linear correlation in all situations without exception, which fulfills certain informal “pre-conditions.” [ABSTRACT FROM AUTHOR]